Gas-enhanced surgical instrument with pressure safety feature

ABSTRACT

A pressure safety system is provided for use with electrosurgical instruments providing pressurized ionized gas to a surgical site. The pressure safety system includes a series of three cascaded pressure change members to control the pressure of gas delivered to a patient. Pressure safety apparatus for use with electrosurgical instruments providing pressurized ionized gas to a surgical site are also provided. Electrosurgical instruments utilizing the pressure safety system and apparatus are also provided. The instruments include a hand-held applicator, a portable actuator assembly and the pressure safety system to control the pressure of gas delivered to a patient.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of and priority tocontinuation-in-part application entitled “GAS-ENHANCED SURGICALINSTRUMENT” filed concurrently herewith, under Express Mail CertificateNo. EV 447675151 US (Atty Doc. 2947 (203-3794 CIP)), which is acontinuation-in-part of U.S. application Ser. No. 11/048,577 entitled“SELF CONTAINED, GAS-ENHANCED SURGICAL INSTRUMENT” filed on Feb. 1,2005, which claims the benefit of and priority to U.S. ProvisionalApplication Ser. No. 60/541,326 entitled “SELF CONTAINED, GAS-ENHANCEDSURGICAL INSTRUMENT” filed on Feb. 3, 2004, the entire contents of eachapplication being incorporated by reference herein.

BACKGROUND

The present disclosure relates to pressure safety systems and apparatusfor use with portable and fixed sources of pressurized ionizable gas.The present disclosure also relates to gas-enhanced surgical instrumentsthat incorporate the pressure safety systems and apparatus for use inopen, laparoscopic or endoscopic procedures.

BACKGROUND OF RELATED ART

Devices, hereafter understood to include instruments for treatingtissue, for example, for tissue division, dissection, ablation, or forarresting blood loss and coagulating tissue are well known. For example,several prior art instruments employ thermic coagulation (heated probes)to arrest bleeding. However, since the probe must come into closecontact with the bleeding tissue, the probe may adhere to the tissueduring probe removal and may possibly cause repeat bleeding. Manysurgical probes also produce an undesirable buildup of eschar on orproximate the probe tip which detrimentally affects the efficiency ofthe surgical instrument. Other instruments direct high frequencyelectric current through the tissue to stop bleeding. Again, escharadherence may occur with these instruments. In addition, with both typesof instruments, the depth of the coagulation is often difficult tocontrol.

Other prior art devices provide a tube-like coagulation instrument inwhich an ionizable gas, for example argon gas, is supplied from a remotegas container or tank to the instrument and ionized by an electrodeprior to the gas being emitted from the distal end of the instrumenttowards the bleeding tissue. The atmosphere of ionized gas isbeneficial, for example, because it helps focus an arc of energyadjacent the electrode and it displaces oxygen from the area and reducesoxidative stress of the tissue. The remotely provided ionizable gas issupplied in large tanks that are typically fixed in one location in ornear an operating room and not in close proximity to the patient so thata long gas supply hose is needed. Often such long hoses add to theclutter in the operating room and are distracting to the operating roomstaff.

Unlike the prior art instruments, the instruments and small gascontainers of the present disclosure are easy to handle and manipulate.These instruments may be configured to include one or more of a varietyof features, e.g., flow and/or pressure regulators, pressure reliefvalves, gauges, indicators, sensors and control systems that can betailored to fit the surgical procedure. The instruments and the controlsassociated therewith may be controlled by hand and/or foot by the userwhich accordingly, provide the opportunity for obtaining optimizedresults. The small gas containers and their contents can also betailored (e.g., in terms of use of a particular inert gas or gasmixture, gas pressure, volume, flow rate, etc.) to fit the particularinstrument and/or procedure also providing the opportunity to obtainoptimized results.

SUMMARY

The present disclosure provides a pressure safety system for use withelectrosurgical instruments providing pressurized ionized gas to asurgical site. In one embodiment, the pressure safety system includes aseries of three cascaded pressure change members. The first pressurechange member has an input side that can be connected to a source ofpressurized ionizable gas and an output side. In the event the gaspressure at the output side of the first pressure change member exceedsa first predetermined value, the first pressure change member isconfigured to release pressurized gas from the system and source intothe environment. The second pressure change member has an input sideconnected to the output side of the first pressure change member and anoutput side. The second pressure change member is configured to inhibitpressurized gas from exiting the output side of the second pressurechange member in the event the gas pressure at the input side of thesecond pressure change member exceeds a second predetermined value. Thethird pressure change member has an input side connected to the outputside of the second pressure change member and an output side. The thirdpressure change member is configured to release pressurized gas from thefirst and second pressure change members and the source into theenvironment in the event the gas pressure at the output side of thesecond pressure change member exceeds a third predetermined value. Itshould be noted that the predetermined values are typically in the samerange. It should also be noted that gas exhausted outside of the patientin a laparoscopic procedure may control or limit the pneumoperitonialpressure.

In one embodiment, the first pressure change member is a pressureregulator having a high pressure side as the input side, a low pressureside as the output side, and a pressure relief member on the lowpressure side. The pressure relief member is configured to open if thegas pressure on the low pressure side exceeds the first predeterminedvalue. As a result, pressurized gas from the system and source ofpressurized ionizable gas can be released into the environment. Thepressure relief member may be a membrane configured to rupture, a valveconfigured to open or any like structure capable of releasing thepressurized gas into the environment.

The second pressure change member is preferably a shut-off valve. In oneembodiment the shut-off valve includes an input port where pressurizedgas enters the shut-off valve, and an output port where pressurized gasexits the shut-off valve. At least one flap capable of blocking theoutput port is provided so that pressurized gas does not exit the outputport in the event gas pressure at the input port exceeds the secondpredetermined value. In an alternative embodiment, a ball and o-ringconfiguration is substituted for the one or more flaps. The ball ando-ring configuration is capable of blocking the output port so thatpressurized gas does not exit the output port in the event gas pressureat the input port exceeds the second predetermined value. The thirdpressure change member is preferably a relief valve that opens torelease pressurized gas into the environment. Alternatively, the thirdpressure change member may be a membrane that ruptures or otherstructure capable of releasing the pressurized gas into the environment.

The present disclosure also provides pressure safety apparatus for usewith electrosurgical instruments providing pressurized ionized gas to asurgical site. In one embodiment, the apparatus includes a housingcapable of receiving a portable source of pressurized ionizable gas anda housing output port for exiting pressurized gas suitable for apatient. A pressure safety system is disposed between the portablesource of pressurized ionizable gas and the housing output port. In analternative embodiment, the pressure safety apparatus includes a housinghaving a housing input port capable of connecting to a source ofpressurized ionizable gas and a housing output port for exitingpressurized gas suitable for a patient. A pressure safety system isdisposed between the housing input port and the housing output port.

The present disclosure also provides gas-enhanced electrosurgicalinstruments for providing ionized gas to a surgical site. In oneembodiment, the electrosurgical instrument includes a hand-heldapplicator, a portable actuator assembly, and a pressure safetyapparatus connected between the hand-held applicator and portableactuator assembly. Preferably, in this embodiment, the hand-heldapplicator has proximal and distal ends and a gas delivery memberadapted to deliver pressurized ionizable gas to the proximity of anelectrode located adjacent the distal end of the hand-held applicator.The portable actuator assembly is capable of receiving a source ofpressurized ionizable gas and has at least one controller that controlsthe delivery of the gas from the supply of pressurized ionizable gas tothe hand-held applicator and controls the delivery of electrosurgicalenergy to the hand-held applicator electrode. The pressure safetyapparatus includes a housing having an input port for connection to thehand-held applicator and an output port for connection to the portableactuator assembly. A pressure safety system having two or more cascadedpressure change members is connected between the housing input port andthe housing output port. The pressure change members are configured torelease pressurized gas into the environment or block the flow ofpressurized gas to the housing output port in the event the pressurizedgas supplied by the portable actuator assembly exceeds a predeterminedvalue. In this configuration, upon actuation of the at least onecontroller, gas from the source of pressurized ionizable gas isdelivered through the pressure safety apparatus to the proximity of theelectrode through the gas delivery member and electrosurgical energy isdelivered to the electrode, such that an ionized gas is emitted from thedistal end of the hand-held applicator.

In an alternative embodiment of electrosurgical instruments, theinstrument includes a hand-held applicator and portable actuatorassembly similar to the applicator and actuator assembly describedabove, except that the actuator assembly includes a pressure safetysystem. In another alternative embodiment, the electrosurgicalinstrument includes a hand-held applicator and portable actuatorassembly similar to the applicator and actuator assembly describedabove, except that the applicator includes the pressure safety system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side schematic view of an electrosurgical coagulatoraccording to the present disclosure;

FIG. 1A is an enlarged view of the encircled portion of FIG. 1;

FIG. 2A is an enlarged, schematic sectional view of an alternateembodiment of a gas cartridge for use with the electrosurgicalcoagulator of FIG. 1 having a color coded identification band and asafety valve;

FIG. 2B is an enlarged, schematic sectional view of a gas cartridge foruse with the electrosurgical coagulator of FIG. 1 having a volume gaugeand a refilling port;

FIG. 2C is an enlarged, schematic sectional view of a gas cartridge foruse with the electrosurgical coagulator of FIG. 1 having a flowregulator;

FIG. 3A is a greatly-enlarged, schematic side view of an iris-like flowregulator for use with the electrosurgical coagulator of FIG. 1;

FIG. 3B is a cross sectional view of the iris-like flow regulator takenalong line 3B-3B of FIG. 3A;

FIG. 4 is a side schematic view of an alternative embodiment of theelectrosurgical instrument according to the present disclosure, showinga hand held applicator and an actuator assembly;

FIGS. 5-5B are perspective, side and frontal views of one embodiment ofthe actuator assembly of FIG. 4;

FIGS. 6 and 6A are perspective views with parts separated of theactuator assembly of FIG. 5;

FIG. 7 is a perspective view with parts separated of one embodiment of agas source module in the actuator assembly;

FIG. 7A is a side cross-sectional view of one embodiment of a gas supplycoupler assembly according to the present disclosure;

FIG. 7B is a perspective view with parts separated of another embodimentof the gas source module in the actuator assembly;

FIG. 8 is a perspective view of the actuator assembly of FIG. 5, with afoot pedal in an open position and showing the gas source module with aportable gas source in a disengaged position;

FIG. 9 is a perspective view of the actuator assembly of FIG. 5, withthe foot pedal in the open position and showing the gas source modulewith the portable gas source in an engaged position;

FIG. 10 is a perspective view of the interior of the actuator assemblyof FIG. 8, showing the gas source module with a portable gas sourcelocking assembly and the gas source in the disengaged position;

FIG. 11 is a perspective view of the interior of the actuator assemblyof FIG. 9, showing the gas source module with the portable gas supply isin the engaged position and the portable gas source locking assemblylocked;

FIG. 12 is a top view of the interior of the actuator assembly of FIG.10, showing a coupler assembly and corresponding portable gas supply inthe disengaged position relative to the coupler assembly;

FIG. 13 is a top view of the interior of the actuator assembly of FIG.11, showing the coupler assembly and corresponding portable gas supplyin the engaged position relative to the coupler assembly;

FIG. 14 is a perspective view of a cross-section of the actuatorassembly of FIG. 5, showing the foot pedal in the open position and thegas source module in the disengaged position;

FIG. 15 is a perspective view of a cross-section of the actuatorassembly similar to FIG. 14, showing the foot pedal in the open positionand the gas source module in the engaged position;

FIG. 16 is a side cross-sectional view of the actuator assembly of FIG.5, showing the foot pedal in the open position and the gas source modulein the disengaged position;

FIG. 17 is a side cross-sectional view of the actuator assembly of FIG.5, showing the foot pedal in the open position and the gas source modulein the engaged position;

FIG. 18 is a side cross-sectional view of the actuator assembly of FIG.5, showing the foot pedal in a closed position and pads attached to thefoot pedal used to actuate gas supply and energy controllers;

FIG. 19 is a side schematic view of an alternative embodiment of theelectrosurgical instrument according to the present disclosure, showinga hand-held applicator with an actuator and the actuator assembly;

FIG. 20 is a perspective view with parts separated of the actuatorassembly of FIG. 19;

FIGS. 21-24 are schematic views of an embodiment of a pressure safetysystem according to the present disclosure in various forms ofoperation;

FIG. 25 is a schematic view of an embodiment of electrosurgicalinstrument showing a pressure safety apparatus and a hand-heldapplicator;

FIGS. 26-26B are schematic views of an embodiment of the pressure safetyapparatus of FIG. 25;

FIG. 27 is a schematic view of an alternative embodiment ofelectrosurgical instrument showing a pressure safety apparatus and ahand-held applicator;

FIG. 28 is a schematic view of an embodiment of the pressure safetyapparatus of FIG. 27;

FIG. 29 is a schematic view of the pressure safety apparatus of FIG. 28;

FIG. 30 is a schematic view of an alternative embodiment ofelectrosurgical instrument incorporating the pressure safety system ofthe present disclosure, showing a hand-held applicator, an actuatorassembly and a pressure safety apparatus between the hand-heldapplicator and the actuator assembly;

FIG. 31 is a top view of the interior of the actuator assembly of FIG.10, showing the pressure safety system incorporated into the actuatorassembly;

FIG. 31A perspective view of a portable source of pressurized gas and acoupler assembly substantially similar to the coupler assembly of FIG.31 with the pressure safety system incorporated into the couplerassembly;

FIG. 32 is a side schematic view of an alternative embodiment of anelectrosurgical instrument similar to FIG. 4, showing the pressuresafety system incorporated into the hand-held applicator and theactuator assembly; and

FIG. 33 is a side schematic view of an alternative embodiment of theelectrosurgical instrument similar to FIG. 19, showing the pressuresafety system incorporated into the hand-held applicator and theactuator assembly.

DETAILED DESCRIPTION

This application discloses embodiments of electrosurgical apparatus orinstruments that are adapted for use with or include a portable supplyof pressurized inert gas for providing ionizable gas to a surgical oroperative site. FIG. 1 shows one embodiment of a gas-enhancedelectrosurgical instrument generally designated 10 having aself-contained supply of pressurized ionizable gas. FIGS. 4 and 19 showdifferent embodiments of gas-enhanced electrosurgical instrumentsgenerally designated 500 and 500′ having portable sources of pressurizedionizable gas remote from the hand-held applicator. The electrosurgicalinstruments of the present disclosure may be used for various surgicalfunctions, such as arresting bleeding tissue, desiccating surfacetissue, eradicating cysts, forming eschars on tumors, or thermicallymarking tissue. For ease of description, the instrument described hereinis configured for use as a coagulator to arrest bleeding tissue.However, those skilled in the art will appreciate that certainmodifications can be made to the electrosurgical instruments of thepresent disclosure so that the instruments can perform other surgicalfunctions without departing from the scope of this disclosure. Moreover,while it is preferable to use argon as the ionizable gas forpromulgating coagulation of tissue, for other surgical functions anotherionizable gas or a combination of ionizable gases may be utilized toachieve the desired result.

Referring to FIG. 1, coagulator 10 is dimensioned to be pencil-like orhand-held, including robotically, for use during open surgicalprocedures, however, it is envisioned that a similar instrument orcoagulator may be configured, for example, with a pistol grip or handledimensioned for laparoscopic or endoscopic surgical procedures. Further,although the basic operating features of an open electrosurgicalcoagulator 10 are described herein, the same or similar operatingfeatures may be employed on or used in connection with a laparoscopic orendoscopic electrosurgical coagulator or instrument, manually orrobotically operated, without departing from the scope of the presentdisclosure. The term “electrosurgical energy” herein refers to any typeof electrical energy which may be utilized for medical procedures.

As shown in FIG. 1, coagulator 10 includes a frame, shown as anelongated housing 11, having a proximal end 12, a distal end 14 and anelongated cavity 15 extending therethrough, for supporting and/orhousing a plurality of internal and/or external mechanical andelectromechanical components thereon and therein. In this disclosure, asis traditional, the term “proximal” will refer to the end of coagulator10 (or other element) which is closer to the user, while the term“distal” will refer to the end which is further from the user.

Distal end 14 of housing 11 includes a distal port 17 which is designedto emit, expel or disperse gas emanating from an elongated gas supplychannel or tube 60 that in this embodiment runs generally longitudinallythrough frame or housing 11 of coagulator 10. Tube 60 is for supplyingpressurized gas 50 to the proximity of an active electrode 350 locatedadjacent distal end 14 of housing 11. Electrode 350 is proximal of port17 such that the gas that is emitted from port 17 is ionized. Elongatedhousing 11 includes a receptacle 25, typically positioned adjacent itsproximal end 12, which receptacle can be or be part of a unitary orintegral handle portion 12 a of housing 11. Receptacle 25 is dimensionedto securely engage and receive or seat a gas pressurized container,canister, cartridge or cylinder 100 therein. Cylinder 100 contains asurgical gas, e.g., a noble or inert gas, or mixture of noble or inertgases. References herein to inert gas or gases are understood to includenoble gas or gases. The preferred inert gas is argon. Cylinder 100 isrelatively small, single use and disposable. The cylinder is ofstandardized design and certified for transportation requirements.Moreover, cylinder 100 is designed and/or sized to be incompatible withother commercial products such as whip cream dispensers and the likewhich use nitrogen and CO2 cartridges for other purposes. Details of gascylinder 100 and its selective engagement with or connection to housing11 are discussed in more detail below with respect to FIGS. 2A-2C.

Elongated gas supply tube 60 is adapted and dimensioned to channel orcarry pressurized gas 50 from cylinder 100 through a regulator or valve30 to or through distal end 14 of coagulator 10 for ionization,typically prior to the gas emitting and dispersing from distal port 17.Regulator or valve 30 can be part of or attached to cylinder 100,housing 11, or actuator 31. It is envisioned that distal port 17 ordistal end 14 may be configured to facilitate or promote the dispersionof the ionized gas plasma 50′ from distal port 17 in a uniform andconsistent manner. For example, distal end 14 may be tapered on one,both or all sides thereof to direct the ionized plasma 50′ towardsurgical or operative site 410. Alternatively, distal port 17 may beconfigured to disrupt or aggravate the dispersion or flow of gas plasma50′ exiting distal port 17 to enhance coagulation by creating a moreturbulent gas flow. It is contemplated that many suitable devices, e.g.,screws, fans, blades, helical patterns, etc., may be employed to causegas plasma 50′ to flow more or less turbulently or with otherpredetermined flow characteristics through tube 60 and/or out of distalport 17.

Elongated housing 11 is connected, for example, by an electrical cable305, to a source of electrosurgical energy generally designated ESU,e.g., an electrosurgical generator 300. As mentioned above, proximal end12 includes a receptacle 25 which receives, securely engages and seatscylinder 100 therein. Receptacle 25 and/or cylinder 100 need not be, asin the case of a single use disposable instrument, but may be configuredto allow cylinder 100 to be selectively removable and replaceable withinreceptacle 25. For example and as best shown in FIG. 1, proximal end 12of elongated housing 11, or receptacle 25 may include a lockingmechanism 40 which upon insertion of a cylinder 100 into receptacle 25automatically (or manually) releasably locks the cylinder 100 securelywithin receptacle 25. By unlocking locking mechanism 40, cylinder 100may be removed and replaced with another cylinder 100.

It is envisioned that the locking mechanism 40 may be any suitabledevice or arrangement, e.g., a collar or clamp which provides adequatelever advantage to set the cylinder 100 against its end seal. The collaror clamp may be designed to allow the cylinder to be disengaged from theseal but retained within the receptacle 25 until the remainingpressurized gas is vented or otherwise relieved. For example, thelocking mechanism 40 may include two or more opposing spring clamps 42a, 42 b which mechanically engage a corresponding one or more notches orcut outs 120 a, 120 b formed in the outer surface of gas cylinder 100.As can be appreciated, upon insertion of cylinder 100 into receptacle35, the spring clamps 42 a, 42 b are positioned to allow entry ofcylinder 100 into receptacle 25 until the spring clamps engage thenotches 120 a, 120 b. It is envisioned that a locking mechanism 40 withspring clamps can be configured and adapted for releasably locking andquickly releasing the locking of cylinder 100 in receptacle 25. It isenvisioned that the cylinder pressure may be used to maintain the endseal.

The relative positioning and mechanical engagement of spring clamps 42a, 42 b in notches 120 a, 120 b fully seats cylinder 100 within thereceptacle such that a distal end 110 of cylinder 100 fully engagesvalve 30. The full seating of cylinder 100 in receptacle 25 can affectpiecing or puncturing of the sealed distal end 110 of gas cylinder 100.Upon opening or actuation of valve 30, gas 50 is dispersed to elongatedsupply tube 60 as explained below.

A variety of other locking mechanisms may be utilized to secure gascylinder 100 to or within receptacle 25. For example, the distal end 110of cylinder 100 of FIG. 1 a may be configured, e.g., threaded (as shownas 110′ in FIG. 2A) to threadedly engage valve 30. Alternatively, asalso shown in FIG. 2A, the proximal end of cylinder 100′ may includethreads 120′ which threadably engage the interior of receptacle 25 (notshown). In this instance it may be advantageous to include or provide arubber O-ring or washer in the proximity of the threads to protectagainst undesirable gas leakage.

Alternatively, proximal end 12 of housing 11 may be adapted to have anexternally threaded collar or sleeve that extends axially outwardly andhave an internally threaded screw closure cap. With a cylinder seated inreceptacle 25, the screw closing of the cap would push cylinder 100distally against the bias of a spring onto an axially disposed piercingmember to thereby break the seal at the distal tip of the cylinder.Removal of the closure cap would permit removal and replacement of thecylinder. The cap can be adapted to safely vent pressurized gas from theinterior of the receptacle 25 should the seal on the distal end of thecylinder be lost or damaged thus preventing the receptacle from burstingin the event of an internal overpressure. Additionally, the cap may beconfigured to include a pressure regulator or valve to control flowthrough seal opening. As can be appreciated, this safety feature may bedesigned to limit the flow from the cylinder and protect the user if thecylinder becomes damaged during handling. Other locking mechanisms arealso envisioned, for example an over-the-center lever arrangement forpulling a yoke around the end of cylinder 100, snap locks, spring lockson the cylinder 100, locking levers, bayonet style locks, and lockingdials or tabs, etc.

The cylinder 100 may also include various ergonomically friendlyfeatures such as rubber gripping elements or contoured walls tofacilitate insertion into the housing 11 and handling especially duringwet operative conditions. The gripping element may be used to helpprevent an accidental falling of the instrument off of or out of thesterile field. Additionally and as described in more detail below, thecylinder may be color coded to specify any or a combination of thefollowing: cylinder contents (gas type and amount); initial pressurereading prior to activation; a specific flow rate; or specify use for agiven procedure.

Electrosurgical instrument 10 includes at least one actuator, e.g., adial or button, generally designated 31, for actuating and selectivelyadjusting the flow of pressurized inert gas 50 from cylinder 100 to theproximity of active electrode 350, and for actuating and selectivelyadjusting the delivery of electrosurgical energy from the source, i.e.,from generator 300, to the active electrode 350 for ionizing the inertgas for use at the surgical site 410. Actuator 31 can also operate asthe actuator for actuating delivery of electrosurgical energy from thesource. Actuator 31 may be referred to herein as the first actuator. Itis envisioned that instead of being located in housing 11, one or moreof the actuators, regulators and/or valves described herein may belocated in a foot switch appropriately connected to coagulator 10.

Electrosurgical instrument or coagulator 10 can also include a secondactuator, here shown as a button-like trigger 20, for actuating thedelivery of electrosurgical energy from the source, e.g., from generator300, through cable 310 and leads 322, 330 to the active electrode 350for ionizing the inert gas for use at the surgical site 410. Trigger 20can be attached to or mounted, for example, on or atop or throughelongated housing 11. Trigger 20 may be any type of known trigger, e.g.,a rocker switch, a handswitch, a footswitch, a slide switch, a dial, abutton, a lever, etc., which, upon actuation thereof, electricallycommunicates with electrosurgical generator 300 to allow the selectivedelivery of electrosurgical energy to active electrode 350.

Active electrode 350 can be attached to or mechanically engaged with thedistal end of the housing and positioned adjacent to or at an operatingsite 410. Active electrode 350 is positioned adjacent the distal end offrame or housing 11 between the distal end of tube 60 and distal port17, although the active electrode can be located just to the exterior ofport 17. For example, active electrode 350 can be mounted to anelongated member that is supported within housing 11 and that extendsoutside of the housing, such that the electrode is positioned justoutside of the port. Active electrode 350 need not be as shown. It canbe a conductive elongated member in the form of a blade, needle, snareor ball electrode that extends from an electrosurgical instrument andthat is suitable, for example, for fulguration, i.e., coagulation,cutting or sealing tissue.

As shown and in most monopolar electrosurgical systems, a returnelectrode or pad 370 is typically positioned under the patient andconnected to a different electrical potential on electrosurgicalgenerator 300 via cable 360. During activation, return pad 370 acts asan electrical return for the electrosurgical energy emanating fromelectrosurgical coagulator 10. It is envisioned that various types ofelectrosurgical generators 300 may be employed for this purpose, such asthose generators sold by Valleylab, Inc.—a division of Tyco HealthcareGroup LP, of Boulder, Colo.

It is envisioned that trigger 20, upon actuation thereof, is designed toenergize electrode 350 in a simple “on/off” manner, e.g., when thetrigger is depressed (or otherwise moved or manipulated, e.g., twisted(dial switch), rocked (rocker switch), or slid (slide switch)).Alternatively, it is contemplated that the electrical intensity fromgenerator 300 may be selectively regulated by trigger 20, such that theuser can alter the electrosurgical effect at operative site 410. Forexample a pressure sensitive trigger or regulator may be utilized tocontrol the amount of electrosurgical energy that is conducted toelectrode 350 which, as described below with respect to the operation ofcoagulator 10, effects coagulation of tissue 400. Triggers and actuatorsthat are contemplated include those such as described in commonly-ownedU.S. Provisional Application Ser. No. 60/424,352 and commonly-owned U.S.application Ser. No. 10/251,606, the entire contents of each of whichare incorporated by reference herein, without intention of being limitedto the same.

U.S. application Ser. No. 10/251,606, now publication No. 04-0092927discloses an electrosurgical instrument having variable controls, ahousing, and an electrocautery blade or electrode extending from thehousing and connected to a source of electrosurgical energy. An actuatorbutton supported on the housing is movable, e.g., depressed, or rockedor slid, from a first position to at least a subsequent position,preferably to a series of discrete subsequent positions wherein eachsubsequent position corresponds to a specific amount of energy beingtransmitted to the blade. A transducer, e.g., a pressure transducer, orother suitable circuit element, is electrically connected between theactivation button and the source of electrosurgical energy. Thetransducer is configured to transmit an electrical output signal (or arange of output signals) to the energy source correlating to theselected movement or position(s) of the activation button. The sourcecorrespondingly supplies an amount or range of electrosurgical energyemission to the blade dependent upon the electrical output signal(s).

The above actuator and selectively adjustable system can be employedusing at least one actuator, actuator 31, for actuating and selectivelyadjusting the flow of pressurized gas from cylinder 100, e.g., viaregulator and valve 30, and for actuating and selectively adjustingdelivery of energy from the source. Such can be achieved by employing,for example, a suitable transistor that produces a signal or two signalsor different sets of output signals based on movement of the actuatorbutton. The signal (or one signal or set of signals) is sent to and issuitable for actuating actuator 31 or regulator and valve 30 to actuatemovement-correlated corresponding selectively adjusted flow of gas fromthe cylinder. The signal (or the other signal or set) is sent to and issuitable for actuating trigger 20 to deliver energy from the source. Asimilar suitable actuator system can be employed with one transistor toactuate a first actuator, actuator 31, for actuating and selectivelyadjusting the flow from cylinder 100, and a second transistor to actuatea second actuator, trigger 20, for actuating and selectively adjustingdelivery of energy from the source. It is envisioned that instead ofbeing located in housing 11, trigger 20 can be located in a foot switchappropriately connected to electrosurgical generator 300 and coagulator10.

It is contemplated that the at least one actuator, e.g., actuator 31, isadapted or operated to actuate the release of pressurized gas 50 priorto actuating the delivery of electrosurgical energy from generator 300.When there is a first actuator and a second actuator, it is contemplatedthat the instrument or coagulator includes one or more elements, e.g.,circuitry, or mechanical or electromechanical mechanism(s), for timingthe flow of gas from cylinder 100 and the delivery of energy to theelectrode. In one particularly useful embodiment, the first actuator isactivated prior to the activation of the second actuator. It isenvisioned that actuator 31 may be activated to dispense pressurized gas50, in the form of argon gas, only for pneumatic dissection procedures.

It is also contemplated that trigger 20 (or generator 300) may cooperatewith one or more sensors 365 which can be attached to instrument 10,housing 11 or electrode 350 and which, for example, continually measuresor monitors a condition at operative site 410, e.g., the amount oftissue coagulation, and relays the information back to generator 300 ortrigger 20. For example, a control system or a safety circuit (notshown) may be employed which automatically (e.g., through a shut-offswitch) reduces pressure or partially closes valve 30 if an obstructionis indicated. Alternatively or in addition, the safety circuit may beconfigured to cut off the energy to tissue 400 and/or activate orrelease a pressure relief valve (e.g., a safety release valve generallydesignated 367) to release the pressure of the pressurized gas basedupon a sensed condition (e.g., an embolic condition or concern) by asensor 365 or by the surgeon. It is also envisioned that based upon thesensed condition, gas cylinder 100, e.g., by valve 30, can be partiallymodulated, inactivated, ejected (or released) from engagement with valvecoupling 32, or valve 30 may be automatically fully de-activated orclosed. Alternatively, sensor 365 may provide feedback to trigger 20 orgenerator 300 to optimize coagulation of the tissue 400 based upondistance from the tissue deduced from the measured back pressure insupply tube 60, based upon tissue type or based upon tissue response. Asecond sensor 321 may be employed to measure the flow of gas 50 throughgas supply tube 60, and may be electrically connected to a flowregulator, e.g., valve 30, to automatically regulate the flow of gasfrom cylinder 100 to electrode 350.

As best shown in FIG. 1, actuator 31 includes regulator and valve 30which is mounted to and through elongated housing 11 and which can bedimensioned to mechanically engage (and preferably also puncture orotherwise engage and open) the sealed outlet at distal end 110 ofselectively removable gas cylinder 100. Gas cylinder 100 can beremovable in a reusable or disposable version of the instrument. In oneparticularly useful embodiment, the mechanical engagement and securementof gas cylinder 100 and valve 30 involves a quick-release type mechanismor other simple attachment mechanism which can be employed on and/or oras part of cylinder 100, receptacle 25 and/or housing 11 to enable theuser to quickly and accurately engage and disengage and remove andreplace gas cylinder 100. For example, various springs, levers, latches,slides and frictional engagement members, (not shown) may be employed tofacilitate loading and quick removal of cylinder 100. As mentionedabove, locking mechanism 40 may be employed to permanently or releasablysecure cylinder 100 within receptacle 25.

Actuation of actuator 31 activates regulator and valve 30. Regulator andvalve 30 selectively controls or regulates the flow of gas from cylinder100 to electrode 350. Regulator and valve 30 may include a cylinderinterface or coupling 32 and a plenum 34. Actuator 31 or regulator andvalve 30 selectively adjusts plenum 34 to selectively regulate theamount or flow of gas 50 from gas cylinder 100, to supply tube 60 and toelectrode 350.

It is envisioned that actuator 31 may be incrementally adjustable (i.e.,rotatable, slideable or pressure sensitive) to provide tactile feedbackto the user relating to the flow of gas 50. As can be appreciated,plenum 34 is disposed between the regulator portion of the regulator andvalve 30 and the proximal end 62 of supply tube 60. As mentioned above,coupling 32 mechanically engages (e.g., threadably engages, snap fits,friction-fits, slide fits, spring mounts, bayonets, or otherwise)cylinder 100, seals the juncture with cylinder 100, and also breaks,pierces or otherwise opens the sealed distal end or outlet of cylinder100 upon insertion of the cylinder 100 into receptacle 25. Although itis preferred that actuator 31 include regulator and valve 30, regulatorand valve 30 can include actuator 31. Regulator and valve 30 may bereferred to herein as a first flow regulator for selectively regulatingthe flow of pressurized gas from cylinder 100.

In one embodiment, coagulator 10 can include separate pressureregulators, valves and/or flow regulators which are separated and spaceddown the length of the coagulator 10. For example, a second flowregulator, e.g., “FR2” may be included which selectively regulates theflow of pressurized gas to electrode 350. In yet another embodiment,coagulator 10 can include a pressure regulator, e.g., “PR”, forregulating the pressure of the pressurized gas that flows to electrode350. Valve 30 may include a pressure regulator having a pressure reliefvalve in communication with cylinder 100 for regulating and/or relievingthe pressure of the pressurized gas in the cylinder. Coagulator 10 alsomay include a flow limiter. For example, valve 30 may include a flowlimiter for limiting the flow of pressurized gas to electrode 350 to aselected level. In one particularly useful embodiment, a pressure reliefvalve or “burp valve” may be included which is disposed proximal to theflow limiter or plenum to permit gas to escape from the channel 60thereby preventing a build-up of pressure at opening 17 as a result ofpartial of full occlusion of opening 17. A flue 430 (see FIG. 1) may beincluded which transfers the relieved gas flow to the proximal end ofthe coagulator 10.

Distal end 110 of cylinder 100 is hermetically sealed when and after itis mounted to and mechanically engaged with coupling 32 to avoidundesirable gas leakage from the mechanical connection. The end seal maybe formed through metal-to-metal contact, by an elastomeric land at theface 110 of cylinder 100 or an elastomeric ring encircling cylinder 100.As can be appreciated, various rubber seals, gaskets, flanges or thelike (not shown) may be employed to accomplish this purpose.

It is envisioned that valve 30 be opened, e.g., manually, to a desiredflow rate prior to activation of electrode 350 to ionize the plasma tocoagulate tissue 400. The same button, actuator or lever that actuatesthe delivery of energy would also activate regulator and valve 30 andthe flow of gas. For example, the movement of a lever would actuateregulator and valve 30 and the flow of gas prior to continued movementof the lever to actuate delivery of energy from the generator 300. It isalso contemplated that actuator 31 or valve 30 may be automaticallyregulated to communicate with trigger 20 and be automatically controlledby activation of trigger 20. For example, the user may select a flowrate by actuating actuator 31 (which may include a visual indicator orthe like to allow the user to readily determine flow rate) such thatupon actuation of trigger 20, regulator and valve 30 initiates the flowof gas 50 through tube 60 to the an ignition point 355 proximateelectrode 350. Electrode 350 can, in turn, be activated to ionize thegas 50 and force the ionized gas plasma 50′ at the tissue or operatingsite 410. Alternatively, actuation of actuator 31 or regulator and valve30 can automatically activate actuation of trigger 20 and flow ofelectrosurgical energy to electrode 350.

After actuation of trigger 20 and initiation of gas flow to ignitionpoint 335, the ignition of the electrode 350 is delayed eithermechanically, electro-mechanically or utilizing delay circuitry or adelay algorithm to preferably enhance delivery of plasma 50′ tooperating site 410. As can be appreciated, the delay circuitry oralgorithm may be incorporated in trigger 20, valve 30 or generator 300.

During use, ionizable gas 50 is supplied under pressure from gascylinder 100 to regulator and valve 30 (or simply a flow regulator) and,upon selective actuation of actuator 31, the gas flows to ignition point335 near electrode 350 where gas 50 is ionized into a gas plasma 50′before being distributed, dispersed or dispensed out of distal end 17 tooperating site 410. During use, the user may selectively alter the gasflow rate and/or the intensity of the energy emanating from electrode350 to meet a desired surgical effect.

Gas cylinder 100 is relatively small and contains an appropriate orsufficient amount gas 50 for a given surgery of short duration. Cylinder100 is typically for single use, and is disposable. It may be replacedas needed during the surgical procedure if it requires a longer ordifferent gas application than provided by a single gas cylinder. As canbe appreciated, different gas cylinders 100 may be utilized fordifferent surgeries which have different gas requirements, e.g., interms of types, amounts, pressures and/or flow rates. The gas pressureof cylinders 100 is typically about 3000 psi or less. Gas cylinders 100have a volume of about 100 cc's or less of gas in the compressed state.

Cylinders 100 containing about 4 liters of gas (at atmospheric pressure)and a flow time of about 2 minutes have been found suitable for atypical coagulation procedure. For such procedures, the flow rateprovided by the cylinder can range from about 0.2 liters/min. to about 4liters/min, and the nominal flow rate may be about 2 liters/min. It isenvisioned that cartridge 100 may be preconfigured to deliver gas at apredefined flow rate, and coagulator 10 may be configured without a flowregulator or flow valve 30 in or on elongated housing 11. Instead,elongated housing 11 may simply include an “open” and “close” switch(not shown) which blocks or releases the flow of gas from the gascylinder 100 depending upon the position of the switch. As a resultthereof, when opened, coagulator 10 relies on the predetermined flowrate of the gas 50 exiting the gas cylinder 100 under pressure.

The gas flow rate employed is dependent upon factors such as theinstrument being used and/or the type of surgery or procedure to beperformed. Different gas cartridges, e.g., cylinder 100′, can bepre-marked or coded, e.g., visibly, with a color, e.g., a colored band150′ (see FIG. 2A) to indicate a specific gas, as-filled flow rate orsuitability for a particular instrument, procedure or application. Thus,a user may pick the appropriate color which specifically relates to adesired specific gas, flow rate and intended surgical use. Sincecylinders 100 are easily replaceable, during surgery the user may opt toreplace a cylinder 100 with a different cylinder 100′ with a differentflow rate (different color band 150′). Cylinder 100 may include a knob,e.g., 100 a at the proximal end of the cylinder to facilitatemanipulation of the cylinder.

FIG. 2A shows an embodiment of a gas cylinder 100′ which includes asafety release pressure stop valve 188′ which is designed toautomatically prevent flow of gas from, cylinder 100′ when the cylinderis removed. More particularly, upon release of the cylinder 100′ fromcoupling 32, a ball 189′ (in a ball check valve) or some other movableobstruction automatically moves distally to block the passage of gas 50through distal end 110′ of the cylinder 100′. Upon insertion orengagement of the cylinder 100′ into coupling 32, a pin or otherprotruding element (not shown) forces ball 189′ proximally to allow therelease of gas 50 from cylinder 100′. As can be appreciated, manydifferent types of release pressure stops may be employed to accomplishthe same or similar purpose and the above-described release pressurestop valve 188′ is only one example. It is contemplated that cylinder100 or the like, e.g., 100′″, can include a safety pressure releasevalve “SPRV” to vent the gas prior to or when an active cylinder 100 isremoved from receptacle 25 and/or to safely control release of cylinderinternal gas overpressure. It is also contemplated that coagulator 10,e.g., receptacle 25, can include a pressure relief valve 440 incommunication with cylinder 100 for relieving the pressure of thepressurized gas in the cylinder.

As best shown in FIG. 2B, an embodiment of gas cylinder 100″ may includea gauge 185″ which measures and indicates the amount of pressurized gasleft in cylinder or used from the cylinder 100″ at any given time. Avisual or audible indicator or sensor (not shown) may be employed toalert the user of a low gas condition. Gas cylinder 100″ may alsoinclude a fill port or refill valve 160″ which enables the user toselectively refill interior 170″ of gas cylinder 100″ without removingthe cylinder from within receptacle 25 of instrument 10.

FIG. 2C shows another embodiment of gas cylinder 100′″ which includes avalve 180′″ disposed thereon which allows a user to selectively regulategas flow from interior chamber 170′″ through distal end 110′″ and tocoagulator 10. As such, a valve would not necessarily be needed withincoagulator 10 and the user can selectively regulate gas 50 by rotating(or otherwise adjusting) valve 180′″ as needed.

FIGS. 3A and 3B show an embodiment of a flow control valve, here shownas a rotary iris-like valve 30′, which may be utilized within coagulator10 (or with the gas cylinder 100′″ as mentioned above) for selectivelycontrolling the flow of pressurized gas from the cylinder. Iris valve30′ may be disposed between a coupling 32′ and a flared portion 62′ ofproximal end 62 of supply tube 60. Upon rotation of iris valve 30′ in afirst direction, a series of interleaved portions 31 a-31 g move toradially reduce or condense the dimensions of passageway or opening 37to limit gas flow therethrough and to the flared portion 62′ of gassupply tube 60. Upon rotation of iris valve 30′ in the oppositedirection, the interleaved portions 31 a-31 g move to radially expandthe dimensions of opening 37, enhancing gas flow therethrough and to theflared portion 62′ of the supply tube 60.

It is envisioned that a corona return electrode or corona startelectrode (not shown, but known in the art) may be utilized withelectrode 350 to initiate a plasma arc. The corona return electrode maybe placed on or within housing 11 located near distal end 14 or distalport 14. The corona return electrode is electrically connected to returnpath 360 of electrosurgical generator 300. The function of the coronareturn electrode is to establish a non-uniform electrical field withactive electrode 350. The non-uniform electric field will cause theformation of a corona near active electrode 350, which will thereby aidin the ignition of gas 50 as it flows out of distal port 17 of thehousing 11. A dielectric member (not shown) may be positioned toseparate active electrode 350 from the corona return electrode.

It is also envisioned that the coagulator 10 may be configured toinclude a two-stage regulator (not shown) instead of a burp valve. Inparticular, this may be particularly advantageous for use with alaparoscopic device wherein the gas flow may be affected by insufflationpressure in the operating cavity.

Moreover, although shown as a pencil-like electrosurgical instrument inthe drawings, it is envisioned that the electrosurgical instrument mayinclude a pistol grip-like handle which enables the user to handle theinstrument like a pistol. It is also contemplated that the cylinder maybe dimensioned for selective engagement (i.e., insertion) within anddisengagement (i.e., release) from the handle. Alternatively, the handlemay be selectively pivotable for handling the electrosurgical instrumentin different orientations, e.g., from an offset position relative to thehousing for handling the electrosurgical instrument in pistol-likefashion to a generally aligned orientation for handling theelectrosurgical instrument like a pencil.

While several embodiments of the electrosurgical instrument describedabove show an internally mounted cylinder 100 that fits withinreceptacle 25 of housing 11, it is envisioned that a portable gas supplymay be used to accomplish the same purpose.

Referring now to FIG. 4, an alternative embodiment of the gas-enhancedsurgical instrument is shown. In this embodiment, a portable gas supplyis provided in a remote actuator assembly 550, here a foot actuatorassembly used by the surgeon. However, the remote actuator assemblycould be a hand operated actuator that is used by another personattending the surgical procedure, such as a nurse.

The surgical instrument 500 in this embodiment includes a hand-heldapplicator 510 and actuator assembly 550. The hand-held applicator 510includes a frame, shown as an elongated housing 514, having a proximalend 516, a distal end 518 and an elongated cavity 520 extendingtherethrough. Distal end 518 of housing 514 includes a distal port 522which is designed to emit, expel or disperse gas emanating from anelongated gas delivery member (here a channel or tube) 524 that in thisembodiment runs generally longitudinally through frame or housing 514 ofapplicator 510. Tube 524 extends from the proximal end 516 of housing514 for connection to supply tube 552 connected to actuator assembly550. Tube 524 is for supplying pressurized gas 50 to the proximity of anactive electrode 350 located adjacent distal end 518 of housing 514.Electrode 350 is proximal of port 522 such that the gas that is emittedfrom port 522 is ionized. At the other end of the housing 514, i.e., itsproximal end 12, a connector 517 is provided so that hand-heldapplicator 510 can be connected to the actuator assembly 550 and, forexample, a source of electrosurgical energy, such as electrosurgicalgenerator 300, via electrical cable 575. A further description of theelectrode and other components of the electrical system of or associatedwith the electrosurgical instrument of the present disclosure isprovided below.

In the embodiment of FIG. 4, active electrode 350 can be attached to ormechanically engaged with the distal end of the housing and positionedadjacent to or at an operating site 410. Electrode 350 is positionedadjacent the distal end of frame or housing 514 between the distal end525 of tube 524 and distal port 522, although the electrode can belocated just to the exterior of port 522. For example, electrode 350 canbe mounted to an elongated member that is supported within housing 514and that extends outside of the housing, such that the electrode ispositioned just outside of the port. Like the embodiment of FIG. 1,electrode 350 need not be as shown. It can be a conductive elongatedmember in the form of a blade, needle, snare or ball electrode thatextends from an electrosurgical instrument and that is suitable, forexample, for fulguration, i.e., coagulation, cutting or sealing tissue.

As shown and in most monopolar electrosurgical systems, a returnelectrode or pad 370 is typically positioned under the patient andconnected to a different electrical potential on electrosurgicalgenerator 300 via cable 360. During activation, return pad 370 acts asan electrical return for the electrosurgical energy emanating fromhand-held applicator 510. It is envisioned that various types ofelectrosurgical generators 300 may be employed for this purpose, such asthose generators sold by Valleylab, Inc.—a division of Tyco HealthcareGroup LP, of Boulder, Colo.

It is envisioned that distal port 522 or distal end 518 of applicator510 may be configured to facilitate or promote the dispersion of theionized gas plasma 50′ from distal port 522 in a uniform and consistentmanner. For example, the distal end 518 may be tapered on one or allsides to direct the ionized plasma 50′ toward the surgical or operativesite 410. Alternatively, distal port 522 may be configured to disrupt oraggravate the dispersion or flow of gas plasma 50′ exiting distal port522 to enhance coagulation by creating a more turbulent gas flow. It iscontemplated that many suitable devices, e.g., screws, fans, blades,helical patterns, etc., may be employed to cause gas plasma 50′ to flowmore or less turbulently or with other predetermined flowcharacteristics through tube 524 and/or out of distal port 522.

Although shown as a pencil-like hand-held applicator in the drawings, itis envisioned that the hand-held applicator may include a pistolgrip-like handle which enables the user to handle the applicator like apistol. The handle may be selectively pivotable for handling thehand-held applicator in different orientations, e.g., from an offsetposition relative to the housing for handling the applicator inpistol-like fashion to a generally aligned orientation for handling theapplicator like a pencil.

Referring now to FIGS. 5-7 one embodiment of the actuator assembly 550will be described. The actuator assembly 550 includes a housing 560having a cover 562 connected to base 564. Cover 562 has an actuator 566,which in this embodiment is a foot pedal pivotably secured to bracket567 (See FIG. 6), used to actuate one or more controllers and topuncture the outlet of the gas supply. In the embodiment of FIG. 4,there are two controllers, one used to control the gas supplied toapplicator 510 and the other used to control the electrosurgical energysupplied to applicator 510.

Referring to FIGS. 6 and 6A the two controllers 568 and 570 are securedto a mounting plate 572 which, in turn, is secured to base 564.Actuation of controller 568 is designed to energize electrode 350 in asimple “on/off” manner, e.g., when the controller is actuated (e.g.,depressed or otherwise moved or manipulated) electrosurgical energy issupplied to the electrode 350. Actuation of controller 570 is designedto allow gas to flow from actuator assembly 550 to applicator 510 (SeeFIG. 6) for discharge to the operative site 410. Controller 570 ispreferably an open and close type valve that permits or blocks the flowof the pressurized gas. When using this type of controller 570 thepressure of the gas in the cylinder 581 is the pressure of the gassupplied to applicator 510. Alternatively, controller 570 may be aregulator/valve assembly that selectively controls and/or regulates theflow of gas from cylinder 581 to applicator 510. It is also envisionedthat controller 570 may be an adjustable valve that controls the flow ofpressurized gas with a rotatable knob, slidable lever or pressuresensitive pad extending from housing 560. The controller 570 may alsoprovide the user with tactile or audible feedback that is indicative ofthe flow of gas. It is envisioned that the alarm may be powered by theflow of gas.

Housing 560 also houses a gas source module 580 that holds a portablesource of pressurized ionizable gas for the surgical procedure beingperformed. Gas source module 580 includes a receptacle 582 configured tosecurely engage, receive, seat or otherwise hold a source of pressurizedionizable gas and to move the gas source between a disengaged positionshown in FIG. 10 and an engaged position shown in FIG. 11. The gassource shown is a cylinder 581 containing pressurized ionizable gas.However, other types of portable containers, canisters, cartridges andthe like are also contemplated. The cylinder 581 shown is similar to thecylinders 100, 100′, 100″ and 100′″ described above. However, since theactuator assembly 550 may be larger than the applicator 510, larger orlonger pressurized containers, canisters, cylinders or cartridges may beemployed to provide more pressurized gas during prolonged use. Detailsof the engagement of cylinder 581 in the actuator assembly 550 arediscussed in more detail below with reference to FIGS. 8-18.

Referring to FIG. 7, receptacle 582 includes a pair of groves 586 thatfit onto rail 588 secured to base 564 so that cylinder 581 is movablebetween the disengaged and engaged positions. A gas source lockingassembly 590 is provided to facilitate movement of receptacle 582 and tolock the receptacle in place when the cylinder 581 is in the engagedposition so as to maintain sufficient pressure on the receptacle 582(and thus the cylinder 581) to ensure that the outlet of the cylinder issealed in coupler assembly 598 and pressurized gas is prevented fromleaking into the housing. Locking assembly 590 includes pivot arm mount592 secured to base 564, pivot arm 594 pivotably secured at one end 594a to mount 592 and pivotably secured to locking arm 596 at end 594 b.End 596 a of locking arm 596 is pivotably secured to receptacle 582 asshown.

Alternatively, as seen in FIG. 7B, the locking assembly 590 may be aratchet mechanism where receptacle 582 includes a series of grooves 620on one or both sides and one or more teeth 622 configured to engage thegroves 620 and lock the receptacle in position are provided on pivotablearms 624. Spring 626 normally biases ends 624 a of arms 624 away fromeach other so that the teeth 622 move toward each other. Springs 628supported by pins 630 on arms 624 engage inner walls of the housing 560and assist spring 626 in normally biasing the teeth 622 toward eachother. To release the teeth 622 from grooves 620, ends 624 a of arms624, which partially extend outside from housing 560 are manuallypressed or crimped so that springs 626 and 628 are compressed and ends624 b of arms 624 spread apart.

The gas source module 580 also includes a coupler assembly 598configured to engage the outlet of the cylinder 581 and provide ahermetic seal around the outlet of the cylinder so that gas does notescape from the coupler assembly. Coupler assembly 598 includes acoupler 600 secured within housing 602 secured to base 564. Coupler 600may be constructed of an elastomeric material so that when the outlet ofcylinder 581 is pressed into port 604 (seen in FIG. 7A) of coupler 600 ahermetic seal forms around the outlet of the cylinder. The interior ofport 604 has a pin 606 used to break, rupture or puncture the seal onthe outlet when a new cylinder is first moved to the engaged position aswill be described below. Coupler 600 also has a channel 608 and an exitport 610 that connects to tube 612 connected to controller 570 (seen inFIG. 12).

It is also contemplated that actuator assembly 550 (or generator 300)may cooperate with one or more sensors 365 that can be attached tohousing 514 of applicator 510 or electrode 350 (seen in FIG. 4). Likethe sensors described above with respect to the embodiment of FIG. 1,sensors 365 can be used to continually measure or monitor a condition atthe operative site 410, e.g., the amount of tissue coagulation, andrelay the information back to generator 300 or actuator assembly 550.For example, a control system or safety circuit (not shown) may beemployed to automatically (e.g., through a shut-off switch) reduce gaspressure or partially actuate controller 570 of actuator assembly 550 ifan obstruction is detected. Alternatively or in addition, the safetycircuit may be configured to cut off the electrosurgical energy totissue 400 (via electrode 350) and/or activate or release a pressurerelief valve (e.g., a safety release valve generally designated 367) tochange the pressure of the gas discharged from the distal end 522 of theapplicator 510 in response to a condition (e.g., an embolic condition orconcern) sensed by sensor 365 or by the surgeon. For example, duringoperation, pressure release valve 367 may be depressed or rotated intohousing 514 to constrict supply tube 524 and reduce the volume of gasdischarged from the distal end 522 of applicator 510.

It is also envisioned that based upon the sensed condition, controller570 may be automatically deactivated or closed. Alternatively, sensor365 may provide feedback to actuator assembly 550 or generator 300 tooptimize performance of the surgical function, here coagulation of thetissue 400, based upon, for example, 1) the distance of the applicator510 from the tissue deduced from the measured back pressure in supplytube 524, 2) tissue type, or 3) tissue response. A second sensor 321 maybe employed to measure the flow of gas 50 through gas supply tube 524,and may be electrically connected to a flow regulator (not shown) toautomatically regulate the flow of gas from cylinder 581 to electrode350.

Referring now to FIGS. 8-18, the operation of the applicator 510 andactuator assembly 550 to supply ionized gas to the operative site 410will be described. Prior to or at the beginning of the surgicalprocedure the actuator 566 is lifted (seen in FIG. 8) and a sealedportable source of pressurized ionizable gas, e.g. cylinder 581, isinserted into receptacle 582 of gas source module 580. As shown in FIGS.8 and 10, when inserting a cylinder the gas source module 580 is in aretracted position where the outlet of the cylinder 581 is not engagedwith coupler 600 of coupler assembly 598. Generally, when in thedisengaged position, locking arm 596 of locking assembly 590 is in aretracted position (seen in FIGS. 14 and 16) so that end 596 b of thelocking arm extends from housing 560 and receptacle 582 is retractedalong rail 588 so that the outlet of cylinder 581 is positioned awayfrom coupler 600. After the cylinder 581 is placed in the receptacle582, end 596 b of locking arm 596 is pushed, preferably in the directionof arrow A (seen in FIG. 16), so that receptacle 582 slides along rail588 in the direction of arrow B (seen in FIG. 17) towards couplerassembly 598 and the outlet of cylinder 581 enters port 604 of coupler600. At this point, actuator 566 can pivot to a closed position (seen inFIG. 18).

To supply ionized gas to the operative site 410 after a cylinder isfirst inserted into the receptacle 582, the seal on the sealed portablesource of pressurized ionizable gas, e.g., cylinder 581, needs to beopened. To puncture (or open) the seal on the outlet of cylinder 581,the user firsts applies sufficient pressure to actuator 566 so thatpressure pads 565 attached to actuator 566 engage end 596 b of lockingarm 596 causing the receptacle to further move along rail 588 so thatthe outlet of cylinder 581 is pressed against pin 606 in coupler 600 topuncture the seal. When the cylinder seal is punctured, end 596 b oflocking arm 596 rests against mount 592, as shown in FIG. 11, so thatthe outlet of cylinder 581 is sealed within coupler 600.

Once the seal in the cylinder is punctured pressurized gas passesthrough channel 608 in coupler 600 and exits the coupler via exit port610 (See FIGS. 10-13). Pressurized gas then passes through tube 612 tocontroller 570. As pressure is being applied by the user to puncture thesealed cylinder, pad 569 attached to actuator 566 engages controller 570(as seen in FIGS. 12 and 18) and actuates the controller causingpressurized gas to flow through tube 614 to port 572 in housing 562 andexit the actuator assembly 550. Similarly, pad 571 attached to actuator566 engages controller 568 (as seen in FIG. 18) and actuates thecontroller causing energy to flow from connector 574 to the electrode350 in the applicator 510. Connector 574 is a conventional electricalconnector used to electrically connect the actuator assembly 550 to thecable 575.

It should be noted that pads 569 and 571 can be dimensioned such that afirst level of pressure causes pad 569 to actuate controller 570 and asecond level of pressure causes pad 571 to actuate controller 568 sothat pressurized gas is provided to applicator 510 prior toelectrosurgical energy being supplied to electrode 350. Alternatively,pads 569 and 571 can be dimensioned so that pressurized gas andelectrosurgical energy are supplied to the applicator 510 at the sametime. To actuate controllers 568 and 570 after the cylinder 581 seal isinitially punctured the user need only apply sufficient pressure toactuator 566 to cause actuation of the controllers as described above.

Referring now to FIG. 19, an alternative embodiment of the applicator510′ and actuator assembly 550′ is shown. In this embodiment, theactuator assembly 550′ includes the controller 570 for controlling theflow of pressurized gas to the applicator 510′, and the hand-heldapplicator includes the controller 568 that controls the energy suppliedto the electrode 350. As a result the cable 575 between the applicator510′ and the actuator assembly 550′ is not needed and the electricalconnections for this embodiment are similar to those described abovewith respect to FIG. 1. Operation of the actuator assembly is similar tothe operation described above, except for the description of controller568 which is not included in this embodiment. During a surgicalprocedure using this embodiment of the electrosurgical instrumentpressurized gas is provided upon actuation of the controller 570 inactuator assembly 550′ and electrosurgical energy is supplied to theelectrode upon actuation of controller 568 in hand-held applicator 510′.

As can be appreciated, use of a remote actuator assembly would allow theuse of a larger gas supply than in the frame or handle of a hand-heldinstrument, thus reducing the number of times that the user would haveto replace the gas supply during prolonged use. Further, the gas supplyhose 552 may be attached to the electrosurgical cable 575 which attachesto the proximal end of the applicator 510 to limit tangling.

It is envisioned that the electrosurgical instrument (i.e., theapplicator and actuator assembly) and the source of pressurizedionizable gas (e.g., cylinder 581) may be completely disposable or theelectrosurgical instrument may be reposable and the gas sourcedisposable. Moreover, the mechanically engaging end of the gas sourcemay be designed for easy retrofit onto exiting electrosurgicalinstruments. It is also envisioned that the applicator 510 and/or 510′can include a second flow regulator (not shown) to regulate the flow ofpressurized gas to electrode 350.

The electrosurgical instrument of the present disclosure may alsoinclude a pressure safety system to control the flow of pressurized gasto the patient. The pressure safety system 700 includes a series ofpressure change members that can relieve or shut-off gas pressure to thepatient. In the present disclosure three pressure change members will bedescribed. However, two or more pressure change members can be utilizedwithout departing from the scope of the present disclosure.

The pressure change members control the flow of pressurized gas to thepatient in a cascading manner, such that if the first pressure changemember does not properly control the gas pressure then the secondpressure change member activates to control the gas pressure. In theevent the second pressure change member does not properly control thegas pressure then the third pressure change member activates to controlthe gas pressure.

FIGS. 21-24 show an exemplary embodiment of a pressure safety system 700utilizing three pressure change members in various forms of operation.The first pressure change member may include a regulator 710 with apressure relief member, the second pressure change member is a shut-offvalve 720, and the third pressure change member is a relief valve 730.The regulator, shut-off valve and relief valve are intended to functionso that pressurized gas below a predefined value exits the pressuresafety system 700 for delivery to a patient. Referring to FIG. 21,regulator 710 has a high pressure side 712 that connects to a source ofpressurized gas at port 713 and a low pressure side 714 that outputspressurized gas at port 715 at a level suitable for a patient. In FIG.21 the source of pressurized gas is a cylinder 718 of pressurized gasthat is similar to cylinder 581 described above. However, it iscontemplated that the source of pressurized gas may be one or moreportable sources of pressurized gas like those described above or afixed source of pressurized gas. In instances where a portable source ofpressurized gas, e.g., cylinder 718, is to be utilized with the pressuresafety system, it is preferable that port 713 in regulator 710 includesa pin configuration (e.g., pin 606 shown in FIG. 7A) for rupturing theoutlet of the cylinder when the cylinder is first inserted into theport. Further, in instances where a portable source of pressurized gas,e.g., cylinder 718, is utilized, port 713 of the regulator 710 may beconstructed of an elastomeric material so that when the outlet of thecylinder 718 engages port 713, a hermetic seal is formed around theoutlet of the cylinder.

A pressure relief member 716 is provided on the low pressure side 714 ofthe regulator 710 and is configured to rupture, tear or otherwise openin the event the gas pressure in the low pressure side of the regulatorexceeds a predetermined value, e.g., ranging between about 10 psi andabout 100 psi. The pressure relief member 716 shown is a “blow-out”membrane that ruptures when the predetermined value is exceeded. Theblow-out membrane is typically made of a material having a known orpredictable rupture specification (i.e., known tensile failure). Forexample, the blow-out membrane may be foil or plastic (e.g., a polymeror the like). The pressure relief member 716 may be a valve, such as arelief valve.

Shut-off valve 730 includes an input port 722 connected to the output ofthe low pressure side 714 of regulator 710 and an output port 724 thatprovides lower pressure gas in the direction of the patient. One or moreflaps 728 are provided in the shut-off valve 720 and are configured todeflect or close when the gas pressure into the shut-off valve exceeds apredetermined value, e.g., ranging between about 2 psi and about 100psi, so that the output port 724 seals and pressurized gas does not exitthrough the output port. The output port 724 includes a flow orifice 726configured to permit the desired flow rate of pressurized gas, e.g.,ranging between about 0.1 LPM and about 5 LPM, to exit the shut-offvalve without affecting the gas pressure level, but permits the flaps todeflect and close in the event the gas pressure exceeds thepredetermined value. In an alternative configuration, a ball and o-ringconfiguration can be substituted for flaps 728 to provide similarfunctionality and to regulate fluctuations in the gas pressure exitingthe shut-off valve 720. It should be noted that the shut-off valve 728can be incorporated directly into the regulator 710, or as shown in FIG.21 the shut-off valve can be a separate component of the pressure safetysystem 700. Relief valve 730 is positioned down stream from the shut-offvalve 720 and is configured to open when the gas pressure in the pathbetween the output port 724 of shut-off valve 720 and the patientexceeds a predetermined pressure level, e.g., ranging between about 0.1psi and about 2 psi.

The operation of the pressure safety system 700 will be described withreference to FIGS. 21-24. In FIG. 21, pressurized gas from cylinder 718enters the high pressure side of regulator 710, is reduced to a lowerpressure level and exits the regulator as shown by the arrow. The lowerpressure gas then passes through the shut-off valve 720 and flows towardthe patient, as shown by the arrow in FIG. 21. Referring to FIG. 22, ifthe regulator fails to reduce the gas pressure on the low pressure side714 of the regulator 710 such that the gas pressure on the low pressureside of the regulator exceeds a predetermined value, e.g., 20 psi,pressure relief member 716 should rupture or otherwise open so thatpressurized gas in the system 700 and cylinder 718 exits through theopen pressure relief member 716. If the pressure relief member 716 failsto rupture or otherwise open then the high pressure gas exiting theregulator 710 and entering the shut-off valve 720 will cause the one ormore flaps (or ball and o-ring configuration) to close so that highpressure gas does not exit the shut-off valve 720, as seen in FIG. 23.In the event the flaps (or ball and o-ring configuration) fail to close,high pressure gas exiting the shut-off valve 720 will exit the pressuresafety system 700 through relief valve 730, as seen in FIG. 24.

Referring now to FIGS. 25-33 various implementations of the pressuresafety system will be described. In FIGS. 25 and 26 the pressure safetysystem 700 is included a housing 740 and the combination is a pressuresafety apparatus. The housing 740 has an opening configured to receivecylinder 718, and a cylinder housing 742 covers cylinder 718 andconnects to housing 740 using, for example, a threaded connection 742 a(seen in FIG. 26A) or a snap-lock configuration 742 b (seen in FIG.26B). When the cylinder housing 742 is connected to the housing 740 theoutlet of the cylinder 718 engages port 713 of regulator 710 and thesealed outlet is ruptured permitting pressurized gas to enter theregulator 710 while sealing the outlet of the cylinder in the port 713to prevent pressurized gas from leaking into the housing 740. Housing740 also includes an output port 744 from which lower pressure gas exitsthe housing 740. In the embodiment of FIGS. 25-26, gas supply hose 748connects to the output port 744 and the hand-held applicator 510 so thatpressurized gas can be supplied to the surgical site. Electrosurgicalenergy is supplied to the hand-held applicator 510 by electrosurgicalgenerator 300 and cable 746. The operation of the pressure safety system700 works in a similar manner as described above. In the eventpressurized gas is released by the pressure safety system into thehousing 740, vent 750 may be utilized to release such pressurized gasfrom the housing.

In FIGS. 27-29, the pressure safety system 700 is included in housing740 and the combination is a pressure safety apparatus. The pressuresafety apparatus is positioned between a fixed source of pressurized gasand the hand-held applicator 510. In this embodiment, the housing 740includes an input port 752 connected to the high pressure side 712 ofthe regulator 710 that is used to connect to the fixed source ofpressurized gas via gas supply hose 749.

In FIG. 30, the pressure safety system 700 is included in housing 740and the combination is a pressure safety apparatus. The pressure safetyapparatus is positioned between the actuator assembly 550, describedabove, and hand held applicator 510′, described above. FIG. 31 shows anembodiment where the pressure safety system 700 is included in theactuator assembly 550. In this embodiment the pressure safety system ispositioned between coupler assembly 598 and controller 570. FIG. 31Ashows another embodiment where the pressure safety system 700 isincluded in actuator assembly 550. In this embodiment, the pressuresafety system is built into the coupler assembly 598 or acts as thecoupler 600 of the coupler assembly 598, where regulator relief valve716 is located on an outer surface of coupler 600, shut-off valve islocated inside coupler 600 and relief valve 730 is positioned near exitport 610 of coupler 600.

In FIGS. 32 and 33 electrosurgical instruments 500 and 500′ which aresubstantially similar to the electrosurgical instruments shown in FIGS.4 and 19 respectively are provided. In these embodiments, the pressuresafety system 700 is located in the hand-held applicator 510 or 510′ andany gas released by the pressure safety system 700 exits housing 514 viavent 754.

Moreover, as noted above, although argon is typically utilized as theionizable gas for promulgating coagulation of the tissue, in some casesit may be desirable to use another ionizable gas or a combination ofionizable gases to affect the same or a similar or different result.

There have been described and illustrated herein several embodiments ofa gas enhanced electrosurgical instrument for arresting bleeding andperforming other surgical procedures. While particular embodiments ofthe disclosure have been described, it is not intended that thedisclosure be limited thereto, as it is intended that the disclosure beas broad in scope as the art will allow and that the specification beread likewise. Therefore, the above description should not be construedas limiting, but merely as exemplifications of preferred embodiments.Those skilled in the art will envision other modifications within thescope and spirit of the claims appended hereto.

1. A pressure safety system for electrosurgical instruments providing pressurized ionized gas to a surgical site, comprising: a first pressure change member having an input side connectable to a source of pressurized ionizable gas and an output side, the first pressure change member being configured to release pressurized gas from the source of pressurized ionizable gas into the environment in the event the gas pressure at the output side of the first pressure change member exceeds a first predetermined value; a second pressure change member having an input side connected to the output side of the first pressure change member and an output side, the second pressure change member being configured to inhibit pressurized gas from exiting the output side of the second pressure change member in the event the gas pressure at the input side of the second pressure change member exceeds a second predetermined value; and a third pressure change member having an input side connected to the output side of the second pressure change member and an output side, the third pressure change member being configured to release pressurized gas from the first and second pressure change members and the source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the second pressure change member exceeds a third predetermined value.
 2. The pressure safety system according to claim 1, wherein the first pressure change member includes a pressure regulator having a high pressure side as the input side, a low pressure side as the output side, and a pressure relief member on the low pressure side which opens if the gas pressure on the low pressure side exceeds the first predetermined value so that pressurized gas from the source of pressurized ionizable gas is released into the environment.
 3. The pressure safety system according to claim 1, wherein the pressure relief member includes a membrane configured to rupture if the gas pressure on the low pressure side exceeds the first predetermined value.
 4. The pressure safety system according to claim 1, wherein the membrane includes at least one of metal foil and a polymer.
 5. The pressure safety system according to claim 1, wherein the pressure relief member includes a relief valve configured to open if the gas pressure on the low pressure side exceeds the first predetermined value.
 6. The pressure safety system according to claim 1, wherein the first predetermined value ranges between about 10 psi and about 100 psi.
 7. The pressure safety system according to claim 1, wherein the second pressure change member includes a shut-off valve.
 8. The pressure safety system according to claim 7, wherein the shut-off valve includes an input port where pressurized gas enters the shut-off valve, an output port where pressurized gas exits the shut-off valve, and at least one flap capable of blocking the output port so that pressurized gas does not exit the output port in the event gas pressure at the input port exceeds the second predetermined value.
 9. The pressure safety system according to claim 7, wherein the shut-off valve includes an input port where pressurized gas enters the shut-off valve, an output port where pressurized gas exits the shut-off valve, and a ball and o-ring configuration capable of blocking the output port so that pressurized gas does not exit the output port in the event gas pressure at the input port exceeds the second predetermined value.
 10. The pressure safety system according to claim 1, wherein the second predetermined value ranges between about 2 psi and about 100 psi.
 11. The pressure safety system according to claim 1, wherein the third pressure change member includes a relief valve.
 12. The pressure safety system according to claim 1, wherein the third predetermined value ranges between about 0.1 psi and about 2 psi.
 13. A pressure safety apparatus for electrosurgical instruments providing pressurized ionized gas to a surgical site, comprising: a housing capable of receiving a portable source of pressurized ionizable gas and a housing output port for exiting pressurized gas for a patient; and a pressure safety system between the portable source of pressurized ionizable gas and the housing output port, wherein the pressure safety system includes: a first pressure change member having an input side connectable to the portable source of pressurized ionizable gas and an output side, the first pressure change member being configured to release pressurized gas from the portable source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the first pressure change member exceeds a first predetermined value; a second pressure change member having an input side connected to the output side of the first pressure change member and an output side, the second pressure change member being configured to inhibit pressurized gas from exiting the output side of the second pressure change member in the event the gas pressure at the input side of the second pressure change member exceeds a second predetermined value; and a third pressure change member having an input side connected to the output side of the second pressure change member and an output side connected to the housing output port, the third pressure change member being configured to release pressurized gas from the first and second pressure change members and the portable source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the second pressure change member exceeds a third predetermined value.
 14. A pressure safety apparatus for electrosurgical instruments providing pressurized ionized gas to a surgical site, comprising: a housing having a housing input port capable of connecting to a source of pressurized ionizable gas and a housing output port for exiting pressurized gas for a patient; and a pressure safety system between the housing input port and the housing output port, wherein the pressure safety system includes: a first pressure change member having an input side connected to the housing input port and an output side, the first pressure change member being configured to release pressurized gas from the source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the first pressure change member exceeds a first predetermined value; a second pressure change member having an input side connected to the output side of the first pressure change member and an output side, the second pressure change member being configured to inhibit pressurized gas from exiting the output side of the second pressure change member in the event the gas pressure at the input side of the second pressure change member exceeds a second predetermined value; and a third pressure change member having an input side connected to the output side of the second pressure change member and an output side connected to the housing output port, the third pressure change member being configured to release pressurized gas from the first and second pressure change members and the source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the second pressure change member exceeds a third predetermined value.
 15. An electrosurgical instrument for providing pressurized ionized gas to a surgical site, comprising: a hand-held applicator having proximal and distal ends, a gas delivery member adapted to deliver pressurized ionizable gas to the proximity of an electrode located adjacent the distal end of the hand-held applicator, the electrode being adaptable to connect to a source of electrosurgical energy; a portable actuator assembly capable of receiving a source of pressurized ionizable gas therein and having at least one controller that controls the delivery of the gas from the supply of pressurized ionizable gas to the hand-held applicator and controls the delivery of electrosurgical energy to the hand-held applicator; and a pressure safety apparatus having an input port for connection to the portable actuator assembly and an output port for connection to the hand-held applicator, and a pressure safety system having two or more cascaded pressure change members connected between the input port and the output port, wherein the pressure change members are configured to release pressurized gas into the environment or block the flow of pressurized gas to the output port in the event the pressurized gas supplied by the portable actuator assembly exceeds a predetermined value; wherein upon actuation of the at least one controller, gas from the source of pressurized ionizable gas is delivered to the proximity of the electrode through the gas delivery member and electrosurgical energy is delivered to the electrode, such that an ionized gas is emitted from the distal end of the hand-held applicator.
 16. An electrosurgical instrument for providing pressurized ionized gas to a surgical site, comprising: a hand-held applicator having proximal and distal ends, a gas delivery member adapted to deliver pressurized ionizable gas to the proximity of an electrode located adjacent the distal end of the hand-held applicator, the electrode being adaptable to connect to a source of electrosurgical energy; and a portable actuator assembly capable of receiving a source of pressurized ionizable gas therein and having at least one controller that controls the delivery of the gas from the supply of pressurized ionizable gas to the hand-held applicator and controls the delivery of electrosurgical energy to the hand-held applicator, and a pressure safety system that controls the pressure of the gas delivered to the hand-held applicator.
 17. The electrosurgical instrument according to claim 16, wherein the pressure safety system includes: a first pressure change member having an input side capable of receiving pressurized gas from the source of pressurized ionizable gas and an output side, the first pressure change member being configured to release pressurized gas from the source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the first pressure change member exceeds a first predetermined value; a second pressure change member having an input side connected to the output side of the first pressure change member and an output side, the second pressure change member being configured to inhibit pressurized gas from exiting the output side of the second pressure change member in the event the gas pressure at the input side of the second pressure change member exceeds a second predetermined value; and a third pressure change member having an input side connected to the output side of the second pressure change member and an output side capable of delivering pressurized gas to the at least one controller, the third pressure change member being configured to release pressurized gas from the first and second pressure change members and the source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the second pressure change member exceeds a third predetermined value.
 18. An electrosurgical instrument for providing pressurized ionized gas to a surgical site, comprising: a hand-held applicator having proximal and distal ends, a gas delivery member adapted to deliver pressurized ionizable gas to the proximity of an electrode located adjacent the distal end of the hand-held applicator, and a pressure safety system coupled to the gas delivery member that controls the pressure of the gas delivered to the proximity of an electrode, the electrode being adaptable to connect to a source of electrosurgical energy; and a portable actuator assembly capable of receiving a source of pressurized ionizable gas therein and having at least one controller that controls the delivery of the gas from the supply of pressurized ionizable gas to the hand-held applicator and controls the delivery of electrosurgical energy to the hand-held applicator.
 19. The electrosurgical instrument according to claim 18, wherein the pressure safety system includes: a first pressure change member having an input side connected to the gas delivery member and an output side, the first pressure change member being configured to release pressurized gas from the source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the first pressure change member exceeds a first predetermined value; a second pressure change member having an input side connected to the output side of the first pressure change member and an output side, the second pressure change member being configured to inhibit pressurized gas from exiting the output side of the second pressure change member in the event the gas pressure at the input side of the second pressure change member exceeds a second predetermined value; and a third pressure change member having an input side connected to the output side of the second pressure change member and an output side connected to the gas delivery member, the third pressure change member being configured to release pressurized gas from the first and second pressure change members and the source of pressurized ionizable gas to the environment in the event the gas pressure at the output side of the second pressure change member exceeds a third predetermined value.
 20. An electrosurgical instrument for providing pressurized ionized gas to a surgical site, comprising: a hand-held applicator having proximal and distal ends, a gas delivery member adapted to deliver pressurized ionizable gas to the proximity of an electrode located adjacent the distal end of the hand-held applicator, and at least one controller that controls the delivery of the gas to the proximity of the electrode and controls the delivery of electrosurgical energy to the electrode; and a pressure safety apparatus capable of receiving a portable source of pressurized ionizable gas, and having an output port for connection to the hand-held applicator and a pressure safety system having two or more cascaded pressure change members connected between the portable source of pressurized ionizable gas and the output port, wherein the pressure change members are configured to release pressurized gas into the environment or block the flow of pressurized gas to the output port in the event the pressurized gas supplied by the portable source of pressurized ionizable gas exceeds a predetermined value; wherein upon actuation of the at least one controller, gas from the portable source of pressurized ionizable gas is delivered to the proximity of the electrode through the gas delivery member and electrosurgical energy is delivered to the electrode, such that an ionized gas is emitted from the distal end of the hand-held applicator.
 21. An electrosurgical instrument for providing pressurized ionized gas to a surgical site, comprising: a hand-held applicator having proximal and distal ends, a gas delivery member adapted to deliver pressurized ionizable gas to the proximity of an electrode located adjacent the distal end of the hand-held applicator, and at least one controller that controls the delivery of the gas to the proximity of the electrode and controls the delivery of electrosurgical energy to the electrode; and a pressure safety apparatus having an input port capable of connecting to a source of pressurized ionizable gas, an output port for connection to the hand-held applicator, and a pressure safety system having two or more cascaded pressure change members connected between the portable source of pressurized ionizable gas and the output port, wherein the pressure change members are configured to release pressurized gas into the environment or block the flow of pressurized gas to the output port in the event the pressurized gas supplied by the portable source of pressurized ionizable gas exceeds a predetermined value; wherein upon actuation of the at least one controller, gas from the source of pressurized ionizable gas is delivered to the proximity of the electrode through the gas delivery member and electrosurgical energy is delivered to the electrode, such that an ionized gas is emitted from the distal end of the hand-held applicator. 